>>109893874Have his henchgirl be one of many criminals who try to exploit Grundy for personal gain, only instead of dying like the rest of them, she ends up falling in Slaughter Swamp and being affected by similar things that created Grundy.
She becomes an undead swamp monster, but instead of becoming a super strong giant with childlike intelligence, maybe the Swamp's chemicals make her retain her intelligence. Hell, maybe even increase it. She becomes not just Grundy's Bride of Frankenstein, but effectively his Dr.Frankenstein. A Grundy wrangler, so to speak.
Grundy doesn't usually have plans for anything other than be left alone and smash shit every now and then, and since we really don't want her to just be Grundy but a girl, you could have her be a real criminal genius on her own right who knows how to push Grundy to do things for her.
She could be the badass female villain writers don't have the balls to let Poison Ivy be anymore.
>>109893926I dig the Bride of Frankenstein idea, especially for her design, but I would also add some other twists.
Since Grundy was basically the Fredric March Mr.Hyde fused with Frankenstein's Monster, Grundy's henchgirl could also take traits from that movie.
Maybe she could transform on and off into her monstrous self in order to better hide into society, unlike Grundy who causes a huge ruckus whenever he goes.